Circuit Protection Devices and its Types

Electricity has become an indispensable part of daily life. But all electrical systems have the potential to cause harm. This is why it is important to use circuit protection devices. If you are planning to buy switchgear and protection devices online, here we answer some of the commonly asked questions on circuit protection devices that you will find useful:

What is a circuit protection device?

A circuit protection device is a current or voltage device that protects a circuit from either overloading, voltage fluctuation, or short circuit.

What devices are used for circuit protection?

Some of the common circuit protection devices are:

Fuses: A fuse cuts the electrical current supply from an electrical circuit when the current in the electrical circuit is too high. It works on the thermal and electrical properties of the conducting materials. It blows out on detecting an overload. It can be used only once and thus needs to be replaced each time it blows out.
Circuit breakers: A circuit breaker is an automatically operated electrical switch. It trips when there is an excess amount of current due, interrupting current flow after a fault is detected. It protects against overloading and short circuits. Unlike a fuse, it can be used multiple times.
Electrical isolators: An electrical Isolator is a switching device that allows you to make or break electric current in a circuit. They are used as a main switch or incomer inside a distribution board. It is used to completely disconnect the circuit from the electrical supply to carry out repair and maintenance work.
MCBs: It is an automatic switch that opens when there is excessive current flowing through the circuit.

How is an MCB different from the fuse?

A fuse stops the current flow in a circuit when the current exceeds its current capacity. While doing so the fuse blows. A blown fuse needs to be replaced whereas a tripped MCB needs to be reset.

What is switchgear?

Switchgear describes a wide variety of switching devices. All these devices together control, protect, and isolate power systems. Switchgear is composed of electrical disconnect switches, fuses, or circuit breakers.

How to choose circuit protection devices?

All electrical installations must be protected against overcurrent or short circuits using circuit protection devices that will operate to prevent injury to persons and damage to the installation. Here are the important factors that must be taken into account when choosing protection devices: